Question about radiator fan... cooling problem

[SVTcobra281]

Hi all, first post here, I'm a mustang guy workin on the wife's '03 WRX for the first time really, so I'm kinda clueless about these cars..

The question is, are both radiator fans supposed to work at the same time? We're having slow overheating problems at idle/slow speeds in hot New Mexico weather. I checked coolant levels and ran the car at 2500rpm for about 5-10 min. On cooldown with keys in ACC position I noticed only 1 fan working. Not sure what the trips both the fans on, I only have 1 fan in the stang

Any help is appreciated guys/gals.

[dumdum]

The second fan should only activate when the A/C is on I believe.I would confirm this of course by letting the car idle with the A/C on.Try using a 66(water)/33(antifreeze) coolant mixture.Also air bubbles in the radiators cause some problems as well due to the coolant tank with cap being above the radiators.Air bubbles get trapped.You have to run the car with the cap off untill the thermostat opens and let the coolant cycle through for a couple minutes.You can squeeze the upper radiator hose to help brup the system.This generally becomes a problem when the coolant gets flushed and refilled.

[SVTcobra281]

Thanks for the reply. I thought that might be the case, so I let it idle with the A/C on and it still wont come on.

Generally the car runs right in the normal range, but it's spiked up a couple of times:

-Once when the wife was sitting in a parking lot with the A/C on at idle in 90+ deg weather

-Once yesterday going up a mountain road behind a slow truck going like 15mph with the A/C on and it was like 90+ deg outside.

I've tried burping any air bubbles out but when I open the radiator cap or the turbo reservoir cap (with car cold of course) all it seems to spit out is a little fluid.

[SVTcobra281]

Well nevermind all.. fixed our problem with a 5 cent part

Looking at the wiring diagram I realized I skipped the most important part of troubleshooting electrical components.. checking the fuse! The main motor fan fuse was blown. I'm guessing that explains our overheating issues.